The largest and least developed section in the JPRS, the 2.6-mile long Main Area extends from the iconic railroad bridge near the Powhite Bridge to the Manchester Climbing Wall and lies between the river and Riverside Drive.

This heavily wooded section includes near-shore islands, side channels, great outcroppings of rocks where you can jump across to Belle Isle, side trails to the shore, the Buttermilk East and Buttermilk Proper trails, meadows, a bug garden next to park headquarters, wetlands, rapids, a kayak and canoe takeout, and a service road giving access to Belle Isle.